I have had constant networking issues with a computer I built. I have this networking card. Whenever it is enabled, it will find the network and join it, but I have no internet. I also can't ping or find other computers on the network. When the card is enabled, my mouse will freeze for a second on the screen when I'm moving it. A guy from school suggested that it might be the range of the router and its causing my processor to work harder. I bought three of these and they did nothing. I got the same amount of signal strength and speed as I did with the stock antennas. I tested them on this and they worked just fine, so I know its not the antennas. I can also stick this card in an HP computer and no matter what antenna it works right away. The problems are only occurring in my bedroom while the computer works just fine in the living room. The HP computer works just fine anywhere. I ran an extension cord from the living room to my bedroom to see if it was the power, and it wasn't. Any help would be great.

Have you tried the card in a different slot on the mobo?
Have you loaded the latest drivers for the card?
Do the power supply cables run near the card? Try to keep them away from the mobo until they reach the plug.

This is a problem found in high frequency radio transmissions, multipath! What is happening is that the radio signal is arriving from the router directly and at the same signal strength from a reflection off of some internal metal in the house itself. the result is the wireless NIC in the laptop receives a packet from the router but it arrives again a split second later. Now the card becomes confused. Repeat that for thousands of packets flying on multiple channels 20 MHz wide and you have a wireless card that can't make head nor tails of the signal! In that room there is a powerful reflection that is as strong as the signal from the router. It's like picket fence on an FM radio signal. If you stop in one of these areas where the distortion occurs, the signal is unintelligible, (totally garbled) .You can try moving the router so that this serious reflections affects another area where you do not take the laptop, but you may never be able to get a decent wireless signal in that room because of this.